I recently restored a SQL 2000 database to my brand new, souped-up SQL 2005 server. Some queries that used to run in under a second in 2000 now take anywhere from 30 to 50 seconds in 2005! I don't understand why this is happening. I can see the execution plans are different (although I'm not quite sure how to read or make sense of the plan). I tried updating all statistics first. When that didn't work I tried rebuilding the indexes. Again, no luck. Any ideas?